Vibrator tuning device



Oct. 29, 1968 E. L. DRAKE I 3,407,698

VIBRATOR TUNING DEVICE 7 Filed April 11. 1966 I 'ELWiN L. DRAKE ATTORNEY I INVENTO R United States Patent 3,407,698 VIBRATOR TUNING DEVICE Elwin L. Drake, 346 Robertson Ave., Battle Creek, Mich. Filed Apr. 11, 1966, Ser. No. 541,800 Claims. (Cl. 84-315) ABSTRACT OF THE DISCLOSURE The present invention relates broadly to a vibrator tuning device for use with a stringed musical instrument, and in its specific phases to a resilient vibrator unit for use on a guitar wherein said resilient vibrator unit comprises a bridge roller mounted on spring members which serve to activate said bridge roller in substantially an up and down direction.

Background of the invention Stringed musical instruments are very old and ancient musical devices and have always been quite prominent and popular in musical circles. Due to electronic development and the rock and roll age, the demand for guitars and other modern stringed instruments has substantially increased in recent years. In many musical groups, the guitar has become the primary musical source helping to produce this constant demand for guitars. Guitars should have flexibility in sound production which can increase their musical range, tone and use. One of the favorite accessories for use with a guitar is a vibrator or tremolo device. There have been many vibrator devices developed over the years. Some have not produced the sound qualities necessary; others have not been able to function as easily as desired. Even having these limitations, some are very complex, expensive, bulky and difficult to manipulate. It was the recognition of these and other problems which led to the present development.

Summary of the invention Accordingly, among the objects of the present invention is the provision of a bridge assembly for a stringed musical instrument having a resiliently mounted spring supporting device and actuation means.

Another object of the present invention is to provide a vibrator device for a stringed musical instrument having a bridge string support assembly which is movable substantially and generally in an up and down direction.

A further object of the present invention is to provide a bridge assembly with a support means having a resiliently mounted rotatable bridge roller unit to support strings of a stringed musical instrument.

A still further object of the present invention is to provide a bridge assembly for a stringed musical instrument having a resiliently mounted string supporting bridge roller member assembly with independent sections supporting the individual strings.

A still further object of the present invention is to provide a bridge assembly which can be frictionally mounted on the top portion of a guitar sound box in such a manner that the tone travel through the bridge member will act on the top portion of the sound box at the most desirable location.

Still further objects and advantages of the present invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, consists of a dual leaf spring bridge assembly supporting a rotatably mounted bridge roller member hereinafter fully described and particularly pointed out in the claims, the annexed drawing and the following description setting forth in detail certain 3,407,698 Patented Oct. 29, 1968 means for carrying out the invention, such disclosed means illustrating, however, but one of the various ways in which the principle of the invention may be used.

- Brief description of drawings In the annexed drawing:

FIGURE 1 is a top plan view of a stringed musical instrument having a bridge assembly attached thereto, illustrating the principles of the present invention.

FIGURE 2 is an enlarged view of the bridge assembly mounted on the stringed musical instrument shown in FIGURE 1.

FIGURE 3 is a partial sectional view taken along line III- III of FIGURE 2, illustrating a bridge shaft and bridge roller assembly of the bridge assembly and its mounting means.

FIGURE 4 is a partial sectional view taken substantially along lines IV-IV of FIGURE 2, illustrating one leaf spring assemby unit of the bridge assemby and its adjusting means.

Description of specific embodiment Referring generally to FIG. 1, there is shown a stringed musical instrument in the form of a guitar 10 which is made up of a sound box 11, a fretted neck 12 and a head member 13. Head member 13 has tension pegs 14 that act on strings 15, the purpose of which is to tune the instrument. Sound box 11 is provided with a top portion 17 having a main sound hole 18, and in the present illustration is shown with auxiliary sound holes 19. At the opposite end of sound box 11 from fretted neck 12 an attaching plate 21 is connected to the sound box 11 and has yoke arms 22 which connect to an anchor member 23. The anchor member 23 secures one end of the strings 15 working in conjunction with the tension pegs 14 to tune the guitar 10.

A bridge assembly 30 is mounted on the top portion 17 of sound box 11. The guitar 10 can be used conventionally or as an electric guitar. When the guitar 10 is operated as an electric guitar, a pickup head 24 is mounted to the bridge assembly 30 by a mounting pin 25. The pickup head 24 is connected to a control member 26 by an electrical wire 27. The control member 26 passes an electrical signal out to an amplifier unit, not shown, through an electrical Wire 28. The bridge assembly 30 has spring support units 31 and 32, as viewed in FIGURES 1 and 2. The spring support units 31 and 32 are connected together for actuation by an actuator bar assembly 33. The units 31 and 32 support a bridge roller assembly 34. The spring support units 31 and 32 can be held together in various ways, in the present illustration they are mounted in spaced relationship by a mounting board 35 and some additional support means as will be explained in more detail below.

Referring generally to FIGURES 2 and 4, spring support units 31 and 32 are positioned apart by notches in mounting board 35 and by the length of bridge roller assembly 34. Referring now to FIGURE 4, spring support unit 31 will be described in detail, and it should be understood that spring support unit 32 will have a similar construction. Spring support unit 31 has a support member 38 mounted in the mounting board 35. A support pad 39 is mounted on support member 38 at its end farthest from mounting board 35 in a preferred embodiment. This mounting pad 39 could be made of various materials. an example of which would be a material made of rubber or other resilient material. Support pad '39 could be mounted to the support member 38 in various manners. The present illustration shows a securing screw 41. A positioning how 42 is provided on supporting member 38 between support pad 39 and mounting board 35, the full purpose and function of which will be explained in more detail below.

1 A leaf spring 43 and a sound conductor 44 are conhected to the support member 38 on the side of position ing bow 42 toward support pad 39 by an adjustment screw 46 acting in conjunction with a securing nut 47. At the opposite end of leaf spring 43 and sound conductor 44 from the adjustment screw 46 endis a bridge shaft support 48 and a stablizer member 49. Securing screws51 are used to mount bridge shaft support 48 to sound conductor 44 and to clamp leaf' spring 43 between stabilizer member 49 and sound conductor 44.

Stabilizer member 49 is provided with a receiving hole 52 which receives a positioning nut 53. A pad member 54, which could be made of various materials such as 'felt, rubber, plastic,'et cetera, is connected to the posi- 'tioning nut 53 and positioned between it and the stabilizer member 49. A positioning screw 55 is securely mounted on support member 38 below the positioning nut 53 and is secured bya lock nut 56. In the present illustration, a wire guide 57 is also secured between positioning screw 55 and the lock nut 56 for supporting electric wire 27 when necessary. Stabilizer member 49 'has a stabilizer extension 61 with a bifurcated head 62, as viewed in FIGURE 2. Bifurcated head 62 acts in conjunction with the actuator bar 33, as will be explained in more detail below.

Adjusting screw 46 is turned down in one direction to cause the leaf spring 43 to move down on the support pad 39 side of positioningbow 42 and to apply pressure 'on the stabilizer member 49 side of positioning bow 42. When adjusting screw 46 moves 'down it applies an up- 'ward pressure on the opposite side of the positioning bow 42 tending to raise the bridge shaft support 48. If the adjustment screw 46 is turned up in the other direction, the pressure on shaft support 48 is reduced. The up- 'per position of the bridge shaft support 48 is determined 'by the position of positioning nut 53 on positioning screw 55. Support unit 31 has just been discussed but, 'as mentioned above, spring support unit 32 is provided with the corresponding parts which act in the same manner as the presently discussed parts of unit 31.

The bridge roller assembly 34 is supported at its ends by the bridge shaft support 48 of spring support unit 31 and its corresponding bridge shaft support 48' of spring support unit 32. The bridge roller assembly 34 can be moved between its up position provided for by positioning nut 53 to various lower positions by the player pushing actuator bar assembly 33 down. This type of actuation will provide for a vibrator sound to be emitted from the guitar 10. In the present illustration, the leaf spring 43 could be made of tempered spring steel, and the sound conductor 44 could be made of a bronze chim. The leaf springs 43 and 43 are provided with bifurcated body portions, as illustrated in FIGURES 2, 3 and 4. 'In some applications only a sound conductor 44 would be needed as long as it had the resilient characteristics 'and sound conducting qualities necessary for the specific application.

1 Referring generally to FIGURE 3, spring support units 31 and 32 are shown supporting the bridge roller assembly 34. The bridge roller assembly 34 has a bridge shaft 64 and a bridge roller 65 and lock nuts 68 and 69. Bridge shaft 64 has threaded ends which are threaded into bridge shaft supports 48 and 48'. The bridge shaft '64 is locked into threaded position in the bridge shaft supports 48 and 48' by the lock nuts 68 and 69, respectively. The bridge roller 65 is supported on the bridge shaft 64 and can rotate about the shaft 64. The bridge roller 65 is provided with slots 71 around its periphery to contact the strings 15. When the activator bar assembly 33 is moved up and down by the player, as explained above, the tension in the strings will vary giving the guitar 10 the vibrator sound desired. In order 4 to reduce to a minimum or eliminate the wear between the strings 15 and their bridge assembly support, the bridge roller 65 is permitted to rotate on the bar shaft '64 providing a rolling action between the slot 71 and the strings 15.

In some applications, it may be desirable to have the strings supported individually by a sectioned bridge roller 65. This would be provided by having each string positioned by a slot 71 in an independent section of the bridge roller 65 which can move independent of the other strings and their independent sections. These independ- 'ent sections are indicated by section lines 72.

The activator bar assembly 33 is provided with an activator bar 75 which has threaded end members. Securing nuts 76 and '77 are turned on the threaded ends of activator bar 75. Threaded end 78 working in conjunction with securing nut 76 is shown in FIGURE 2. The threaded ends of the activator bar assembly 33 are positioned between the bifurcated heads of spring supportunits 31 and 32, and the securing nuts 76 and 77, respectively, are then tightened down holding the activator bar '75'inposition. This gives flexibility and ease in removing the bridge assembly 30 from the guitar 10, and is desirable in storing the guitar 10 in its carrying case.

Referring generally now to FIGURES 2 and 4, the tension with which spring support units 31 and 32 support the bridge roller assembly 34 is determined by the combination action of the positioning nuts 53 and 53' and the adjustment screws 46 and 46'. The securing nut 47 can be secured in a non-rotating manner on the underside of support member 38. The adjustment screws 46 and 46' can be turned down so that the leaf springs 43 and 43 will provide the desired upward pressure on the bridge shaft supports 48 and 48. The positioning nuts 53 and 53' will then be positioned on their positioning screws so that the bridge roller 65 will position the strings 15 at the desired elevated height above the top portion'17 of guitar 10. The player Will then tune the individual strings 15 by using tension pegs 14 in the normal manner used in this art. The positioning nut 53 is desirable in the preferred application to dampen the vibration of the bridge shaft support 48. This permits the player to acquire the proper sensitivity of the vibrator effect when he moves the activator bar assembly 33 down from its upper position and then releases or raises it.

In some applications a less complex and a less expensive vibrator device may be desirable. In one particular case,-the support member 38 would extend from the mounting board 35 and would only contact the top portion 17 through mounting board 35, thus eliminating the support pad 39. In some applications there would be no need for an adjustment-screw system such as illustrated by adjustment screw 46. Also, the invention of this embodiment could be made to eliminate the positioning nut 53 with the bridge roller 34. The position of the bridge roller assembly 34-would be determined by thetension pegs 14 put on the strings 15. This would permit movement of the bridge roller assembly 34 in both an up and a down direction from its normal position when the operator is moving and releasing the actuator bar 75. There would also be the'possibility of having an embodiment with a positioning nut 53 without an adjustment screw 46, or an adjustment screw 46 without a positioning nut 53. As can well be appreciated, various combinations of these embodiments could be arrived at and be preferred by various users.

It Will be seen from the above, that simple and inexpensive yet practical and durable means have been disclosed for attaining the desired ends. Attention is again invited, however, to the possibility of making variations within thespirit and scope of the invention set forth. Also, directional terms such as upward, downward, up and down have been used to expedite explaining the invention in the position shown in the drawing and are not to be considered as limiting the invention.

Other modes of applying the principle of my invention may be employed instead of those explained, change being made as regards the means and mechanism herein disclosed, providing the features stated by any of the following claims or the equivalents of such stated features be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A string supporting bridge assembly for a stringed instrument such as a guitar, said instrument including a sound box with a top portion and a means anchoring a set of strings comprising, in combination therewith,

(a) a bridge assembly mounting means positioned on said top portion,

(b) a bridge roller member positioned laterally and separate from said anchoring means above said top portion and supporting said strings,

(c) a resilient support means positioned on said mounting mean and supporting said bridge roller assembly, and

(d) an actuator bar assembly connected to said resilient support means to activate said bridge roller member in substantially an up and down direction.

2. A string supporting bridge assembly as defined in claim 1 wherein (a) said resilient support means having two spring support units positioned on said mounting means, one of said units disposed on each side of said set of strings,

(b) said spring support units comprising a lower support member contacting said mounting means, a spring member mounted on said lower support member and an upper support member secured to said spring member to support the said bridge roller assembly.

3. A string supporting assembly as defined in claim 2,

wherein said spring units include (a) support pads mounted to said lower support members and contacting said top portion.

4. A string supporting assembly as defined in claim 3,

wherein said spring units include (a) positioning members acting on said spring member to limit their upward movement.

5. A string supporting assembly as defined in claim 4,

wherein said bridge roller assembly includes (a) a bridge shaft, and

(b) a bridge roller having slots to receive said strings is rotatably mounted on said bridge shaft.

6. A string supporting assembly as defined in claim 5,

wherein (a) said bridge roller includes a plurality of sections wherein each section supports at least one of said strings independently from other of said strings. 7. A string supporting assembly as defined in claim 6, wherein (a) said actuator bar assembly is releasably connected to said spring members. 8. A string supporting assembly as defined in claim 2, wherein said spring units include (a) positioning bows on said lower support members, (b) said spring members in contact with said position ing bows, (c) adjusting means connecting said spring members to said support members, and (d) said adjusting means to assist in controlling the tension said spring members place on said bridge roller assembly. 9. A string supporting assembly as defined in claim 8, wherein said spring units include (a) stabilizer extensions connected to said spring members,

(b) positioning members acting on said stabilizer ex tensions to limit the upward movement of said spring members,

(c) said stabilizer extensions having bifurcated head members, and

(d) said activator bar assembly being releasably connected to said stabilizer extensions by having a threaded end positioned at said bifurcated head member and having a nut locking in its place.

10. A string supporting assembly as defined in claim 9, wherein said bridge roller assembly includes (a) bridge shaft supports secured to said spring members,

(b) abridge shaft,

(c) lock means on said bridge shaft to secure it to said bridge shaft supports, and

(d) a bridge roller rotatably mounted on said bridge shaft and having slots to receive said strings.

References Cited UNITED STATES PATENTS 1,716,747 6/1929 Warner 84-313 3,185,011 5/ 1965 Anderson 84-267 3,251,257 5/1966 Bunker 84-267 2,905,042 9/1959 Hoyer 84-307 2,152,783 4/ 1939 Beauchamp 84-313 RICHARD B. WILKINSON, Primary Examiner.

G. M. POLUMBUS, Assistant Examiner. 

